Large off-highway machines, such as, for example, mining trucks, are known to employ electric drive systems to propel or retard the machine. Typically, an electric drive system includes a generator, or other electrical power generator, such as an alternator, driven by an internal combustion engine. The generator, in turn, supplies electrical power to one or more electric drive motors connected to wheels or ground engaging tracks of the machine. It should be appreciated that a significant amount of heat is generated during the operation of the electric drive system. Specifically, the generator and the electric drive motors, along with various other electrical components, may generate a significant amount of heat and, as such, may require cooling and/or monitoring to prevent damage or failure. Although temperature sensors may be provided for some components of the electric drive system, the use of temperature sensors for rotating components, such as the generator rotor, may not be feasible due to cost and reliability concerns.
U.S. Pat. No. 7,099,793 to Rechberger appears to disclose a method for estimating a rotor temperature based on generator voltage and a static temperature characteristic map. Specifically, a field weakening controller and a limiter, along with input from a plurality of phase current sensors, are used to generate a voltage signal. This voltage signal, along with the static temperature characteristic map, is used to estimate the rotor temperature. Although a temperature estimate may be determined, the method of the Rechberger reference does not appear to account for additional parameters that may have an impact on rotor temperature.
The present disclosure is directed to one or more of the problems set forth above.